Electric-lamp-supporting device.



R. H. RUTH. ELECTRIC LAMP SUPPORTING DEVICE.

APPLICATION FILED NOV. 24,1913- Patented July 30, 1918.

2 SHEETS-SHEET l.

A wn 9 5 R. H. RUTH.

ELECTRIC LAMP SUPPORTING DEVICE;

APPLI CAT|0N FILED NOV. 24. 1913.

1 274,202. v Patented July 30, 1918.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE- ROBERT H. RUTH, OF NEW YORK, N. Y., ASSIGNOR T0 BENJAMIN ELIECTRIC MANUFAC- TURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ELECTRIC-LAMP-SUPPORTING DEVICE.

Specification of Letters Patent.

Patented July 30, 1918.

Application filed November 24, 1913. Serial No. 802,826.

To all whom it may concern: 4

Be it known that 1, ROBERT H. RUTH, a citizen of the United States, residing at New York city, in the county of New York and State of New York, have invented new and useful Improvements in Electric-Lamp-Su-pporting Devices. of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention pertains to electric lamp supporting devices, and relates especially to extension sockets, 2'. e., sockets which are provided with an extension plug adapted to be inserted into a wall fixture, ceiling fixture or the like. It is one of the objects of my invention to provide an improved form of socket in which means are provided for preventing accidental displacing, or unauthorized removal, of the lamp. It is another object of my invention to provide an improved form of extension socket in which means are provided for preventing accidental displacing, or unauthorized removal, of either the lamp or the socket. .Another object of the invention is to improve upon the constructional features of the lamp retaining means for the socket and of the means for securing the plug portion thereof in position. Other and further objects of the invention will appear from the following specification, taken in connection with the appended claims.

I have described in the following specification, and' shown in the accompanying drawings, one form of lamp supporting device embodying my invention. I wish it understood, however, that the construction shown and described is only one example of the many constructions in which the invention may be embodied, and that changes may be made in the construction shown and described, without exceeding the scope of the invention, as defined in the appended claims.

In the drawings: 1

Figure 1 is a longitudinal section through an extension socket embodying my invention;

Fig. 2 is a top plan of the same;

Fig. 3 is a horizontal section on the broken line 3-3 of Fig. 1, looking in the direction of the arrows;

Fig. 4 is a horizontal section on the line 4-4 of Fig. 1,-looking in the direction of the arrows; I

Fig. 5 is a detail perspective view of one of the plug-retaining spring tongues;

Fig. 6 is a detail perspective view of one of the cam-washers;

Fig. 7 is a perspective view of the lampretaining device, showing same separated from'the socket;

Fig. 8 is a horizontal section taken on the line 8-8 of Fig. 1, looking in the direction of the arrows; and

Fig. 9 is a detail section taken on the line 9-9 of Fig. 1, looking in the direction of the arrows.

Like reference characters refer to like parts throughout the following specification and the several figures of the accompanying drawings.

-The extension socket now being described is made in two relatively movable parts; and the plug portion of. the socket is provided with a plurality of spring ton es adapted to be forced outward, so as toaite into the material of the receptacle shell, when one of the socket portions is moved toward the other. The means for efi'ecting the relative movement of the socket portions is located in the material of the socket; and is thus inaccessible when a lamp is present in the socket. Thus the socket portions cannot be moved away from each other therebyreleasing the spring tongues from their ongagement with the receptacle shell, unless the lamp be removed first. Means are provided for preventing the removal of the lamp from the socket by unauthorized persons.

Referring now to the drawings, and particularly to Figs. 1-6, the extension socket includes an insulating block 10, having formed therein a chamber 11 for receiving the threaded contact, etc., of the socket. and having projecting upwardly therefrom a plug portion 12, the portion 12 being formed with an upwardly extending boss 13 (Fig. 3). The threaded lamp-engaging contact 14 is secured in place by means of screws 15 passing longitudinally through the plug portion 12 and having nuts 16 at their upper ends. One of these screws 15 is somewhat longer than the other, this being necessi tated by reason of the provision of the boss 13. Clamped beneath the nuts 16 are a pair of cam-washers 17, having downwardly inclined lugs 13, the purpose of which will appear below. The lugs 18 lie in recesses suitably formed in the sides of the plug portions 12.

Cooperating with the socket portion described above, is a second portion which includes an insulating button 19 having mounted thereon a threaded contact 20 of such length as substantially to cover the plug portion 12, when the two portions of the socket are put together. Thethrcaded contact 20 is provided with an inwardly extending flange 21 which lies in a corresponding depression formed at the top edge of the button. 19. The flange 21 is formed with an inwardly projecting ear 22, which lies in a corresponding depression of the button 19, and prevents relative rotation between the threaded contact 20 and the button 19. The threaded Contact is retained in position by means of an insulatingwasher 23, preferably formed or fiber which overlies the flange 21 and is secured in place by means or" a hollow rivet 2e, beneath the upper end of which it is clamped. Beneath the upper end of the rivet 24 is also clamped a U-shaped spring center contact 25. The lower end of the rivet 2i lies in a suitable depression formed in the button 19, so as to be flush with the. bottom surface of the latter. The bottom surface of the insulating button 19 is formed with a depression 26 for receiving the boss 13 of the plug portion 12, and is provided with other depression for receiving the nuts 16. lit will be seen that, by reason of the engagement of the boss 13 the depression 26, relative rotation between the socket portion is prevented, even when these portions are comparatively loose with respect to each other in a longitudinal direction. The boss 13, Coiiperating with the depression 26, likewise enforces the placing of the parts together 'i the proper position of rotation with respect to each other.

The boss 13 is of a height equal to onehalf the oistanco between the threads of the threaded contact 20, so that each oi the cam-washers 11' occupies the same position with relation to the threads of said contact. Secured to the inner side of the threaded contact 20 are a pair of resilient tongues 27,, the tendency of which is spring inward. These tongues are provided with outwardly extending points which pass through the material of the shell 20. The spring tongues 21' are disposed in cooperat've relation with the cam-washers 17, and 4 I 1 such position that their points 28 en ac anus tend outward through the top portion of the thread of the contact 20.

The insulating block 10 is formed, within the chamber 11, with a central boss 29 having, at the end thereof a depression for receiving a washer 30. Passing longitudinally through the plug portion 12, is a screw 31, the head of which, with the washer 30, forms the center contact of the socket. The screw 31 enters the hollow rivet 24, which latter is internally threaded to receive it. It will be seen that, by tightening or loosening the screw 31, the. insulating button 19, carrying with it the contact 20 with its spring tongues 27, may be moved toward or away from the plug portion 12. When the plug portion 12 is moved toward the insulating button 19, the lugs 18 of the cam-washers 17 will, by their inclined engagement with the spring tongues 27, force the latter outward. When the button 19 is moved away from the plug portion 12, the spring tongues 27 are permitted to spring inwardly.

In the use of the device, when it is desired to insert the extension socket into a wall receptacle, ceiling receptacle or the like, the screw 31 is first loosened, and the plug portion 12 pulled away slightly from the button 19. This permits the spring tongues 27 to spring inwardly, their points 28 disappearing within the threaded contact 20. 'l fith the parts of the extension socket in this condition, the plug portion thereof is screwed into the receptacle fixture, the engagement of the boss 13 in the recess 26 preventing turning movement of the plug portion 12 with respect to the button 19 during this operation. f hen the plug portion of the socket has been screwed firmly home into the receptacle fixture, the screw 31 is tightened, thus moving the pi portion 12 toward the button 19. The effect of such movement of the plug portion 12 is that the inclined lugs 18 of the cam-washers force the spring tongues outwardly, so that their points 28 immerge beyond the threaded contact 20 and bite into the material of the threaded contact of the fixture receptacle. When the spring tongues 2'? have thus been forced outwardly, the plug portion of the extension socket is definitely and firmly locked against withdrawal from the fixture receptacle, and can only be released when the screw 31 is loosened to permit the tongues 27 to spring inwardly. lit will be seen that, when a lamp is present in the extension socket, the screw 31 cannot thus be loosened, it being necessary first to re move the lamp before the screw 31 can be operated to permit the extension socket to be withdrawn from the fixture receptacle. hie-ans are provided for preventing the removal of the extension socket, except by authorized parties; and such means will now be described.

Referring particularly to Figs. 1 and 7 to 9, the insulating block 10 is formed with a horizontal slot 33 through the side thereof, which slot opens, at its center, into the chamber 11. The slot 33 is formed with a curved wall 34 at its outer side, and with a fiat wall 35 at its inner side. Removably mounted in the slot 33 is a lamp retaining memberwhich will now be described. The lamp retaining member (see particularly Fig. 7) includes an insulating strip 36, formed of fiber or the like to the front surface of which is riveted a metallic plate 37, preferably of. steel, having a plurality of teeth 38 stamped upw'ardly thereupon, such teeth being of a width substantially equal to the distance between two of the threads of a lamp base. Secured to the rear side of the strip 36 is a second substantially similar 1 strip 39, which covers and insulates the heads of the rivets which secure the plate 37 to the strip 36. Secured t0 the strips 36 and-39, by means of a rivet 40, is a curved leaf spring 41, one end of which is free. The strips 36 and 39 are formed, at one end, with enlargements, which together produce a head 42; and these strips are formed, at the opposite ends, with a hole 43 for receiving a padlock or the like 44,. Normally,

I the lamp retaining member is in place in the slot 33, with its head 42 in engagement with one side of the block 10, and with the padlock is in place. The teeth 38 then face in the direction of rotation in which the lamp base is turned in screwing it into the socket.

When a lamp is screwed into the socket, its base engages against the inclined faces of the teeth 38 and slides thereover, forcing the retaining member backward, against the action of the spring 451. The lamp may thus readily be inserted into the socket. ll an attempt is made, however, to remove the lamp after it has once been inserted, the teeth 38 will bite in the material or the lamp base, and efiectually prevent the lamp from being removed. The teeth 38 likewise prevent the lamp from shaking loose in the socket. When it is desired to remove the lamp, this can be done by an authorized person, who alone would be in possession of a key to the padlock 44, by removing the padlock and then sliding the lamp retaining member out of the slot 33. The lamp can then readily be taken out'of the socket,

thus permitting the socket itself to be removed from the fixture receptacle, if desired.

it will be seen that the extension socket which 1' have described as an embodiment of my invention efiectively prevents theft of the socket, or of the lamp contained therein.

Likewise the socket cannot become farred loose. nor can the lamp become jarred oose, by reason of vibrations to which the socket may besubjected. For this reason, apart its theitprooi qualities, the socket is of considerable value for use in railroad cars, factories, and other places where it would be subjected to vibration. The socket is of a simple and economical construction, many of the parts being duplicates and being susceptible of production by the economical stamping and spinning processes; and the parts are so made and arranged that the socket will be durable in use.

While I have described and shown, as an example, one form which my invention may take, I wish it ,to be understood that the invention may be embodied in numerous other constructions than that explained above, and that changes may be made in the mechanical details of the construction which has been described and shown, what I claim being:

1. An extension socket including a socket portion and a plug portion, releasable means, operable from the interior of the socket portion, for retaining the plug portion in a receptacle, and means carried by said extension socket for operating said releasable means.

2. An extension socket including a socket portion and a plug portion, means for releasably locking said plug portion in a receptacle, and means, operable from within the socket portion, for operating said first named means, comprising a screw carried by said extension socket.

3. The combination with two relatively movable members, of a threaded contact associated with said members, a device, asso ciated with said contact, for engaging and looking a second threaded contact, said device coiiperating with said members so as to be movable into and out of operative position according as said members are moved in one direction or the other with respect to each other, and means for effecting a relative movement of said members.

a. The combination with a pair of relatively movable members of a threaded contact associated with said members, a looking device, associated with said contact, cooperating with said members so as to be moved into or out of operative condition according as said members are moved toward or away from each other, and means for efiecting a relative movement of said members.

5. An electric lamp supporting device comprising a portion for insertion into a lamp socket, means for locking said portion in said socket, and means for operating said locking means including a screw which also forms a central contact for engagement with a lamp contact v 6. An electric lamp supporting device comprising a member carrying a central contact for engagement with the central contact of a lamp socket, a second member 7 movable relative to said first member, a screw engaging said central contact and also engaging said second movable member for In Witness whereof, I have hereunto subcausmg relative movement of said members, scribed my name 1n the presence of two wltsald screw forming a central contact for nesses.

engagement with a lamp contact, and means ROBERT H. RUTH. 5 for locking said device in a lamp socket actu- Witnesses:

Y ated by the relative movement of said mem- BASIL G. RODJFANOFF,

bers. ARNOLD SCHINEIDLER. 

